8. Air Calibration
(a) Hang the Dissolved Oxygen sensor in air. The tip of the sensor
should be pointing downwards.
(b) Allow the reading to stabilise. After a zero calibration, this may
take up to 5 minutes.
(c) Press and hold the key for 2 seconds to calibrate.
(d) A “ “ in the display will be replaced by a decimal point after a
successful air calibration.
9. The Aqua-DP is now calibrated for Dissolved Oxygen and is ready
for use in the mode that was selected during calibration.
NOTES:
When taking sample measurements, always ensure that there is
adequate flow of solution past the membrane for accurate, stable
readings. See section 12.1.6.
If salinity-corrected ppM Dissolved Oxygen readings are required, set
the salinity correction value before taking sample measurements.
See section 7.
3.2 Dissolved Oxygen Calibration Notes
1. A zero calibration should be performed at least monthly. In
applications where there is a low level of dissolved oxygen, a zero
calibration may have to be done weekly.
2. An air calibration should be performed at least weekly. Of course,
more frequent calibration will result in greater condence in results.
3. All calibration information is retained in memory when the Aqua-DP is
switched off, even when the battery is removed.
4. The salinity correction value is ignored during zero and air calibration.
There is therefore no need to re-set the salinity correction value when
calibrating Dissolved Oxygen.
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